1. 23 Jul, 2016 1 commit
  2. 04 Dec, 2013 1 commit
  3. 17 Oct, 2013 2 commits
  4. 21 Nov, 2012 1 commit
  5. 27 Jul, 2011 3 commits
    • Hans Verkuil's avatar
      [media] v4l2-event/ctrls/fh: allocate events per fh and per type instead of just per-fh · f1e393de
      Hans Verkuil authored
      The driver had to decide how many events to allocate when the v4l2_fh struct
      was created. It was possible to add more events afterwards, but there was no
      way to ensure that you wouldn't miss important events if the event queue
      would fill up for that filehandle.
      
      In addition, once there were no more free events, any new events were simply
      dropped on the floor.
      
      For the control event in particular this made life very difficult since
      control status/value changes could just be missed if the number of allocated
      events and the speed at which the application read events was too low to keep
      up with the number of generated events. The application would have no idea
      what the latest state was for a control since it could have missed the latest
      control change.
      
      So this patch makes some major changes in how events are allocated. Instead
      of allocating events per-filehandle they are now allocated when subscribing an
      event. So for that particular event type N events (determined by the driver)
      are allocated. Those events are reserved for that particular event type.
      This ensures that you will not miss events for a particular type altogether.
      
      In addition, if there are N events in use and a new event is raised, then
      the oldest event is dropped and the new one is added. So the latest event
      is always available.
      
      This can be further improved by adding the ability to merge the state of
      two events together, ensuring that no data is lost at all. This will be
      added in the next patch.
      
      This also makes it possible to allow the user to determine the number of
      events that will be allocated. This is not implemented at the moment, but
      would be trivial.
      Signed-off-by: 's avatarHans Verkuil <hans.verkuil@cisco.com>
      Signed-off-by: 's avatarMauro Carvalho Chehab <mchehab@redhat.com>
      f1e393de
    • Hans Verkuil's avatar
      [media] v4l2-events/fh: merge v4l2_events into v4l2_fh · 523f46d6
      Hans Verkuil authored
      Drivers that supported events used to be rare, but now that controls can also
      raise events this will become much more common since almost all drivers have
      controls.
      
      This means that keeping struct v4l2_events as a separate struct make no more
      sense. Merging it into struct v4l2_fh simplifies things substantially as it
      is now an integral part of the filehandle struct.
      Signed-off-by: 's avatarHans Verkuil <hans.verkuil@cisco.com>
      Signed-off-by: 's avatarMauro Carvalho Chehab <mchehab@redhat.com>
      523f46d6
    • Hans Verkuil's avatar
      [media] v4l2-ioctl: add ctrl_handler to v4l2_fh · 2d28b686
      Hans Verkuil authored
      This is required to implement control events and is also needed to allow
      for per-filehandle control handlers.
      Signed-off-by: 's avatarHans Verkuil <hverkuil@xs4all.nl>
      Signed-off-by: 's avatarMauro Carvalho Chehab <mchehab@redhat.com>
      2d28b686
  6. 22 Mar, 2011 3 commits
  7. 19 May, 2010 2 commits